1. Field of the Invention
The invention relates in general to a method of registering a network, and a mobile station and a communication system using the same, and more particularly to a high-security method of registering a network, and a mobile station and a communication system using the same.
2. Description of the Related Art
U.S. Patent Publication No. 2002/0009199 discloses architecture and a method of registering a wireless local area network (WLAN). FIG. 1 (Prior Art) is a schematic illustration showing a conventional communication system 100. As shown in FIG. 1, a general packet radio service (GPRS) network 120 in the communication system 100 includes a base station (BS) 122, a radio access network (RAN) 124, a mobile switching center/home location recorder (MSC/HLR) 126 and a verification database 128. The mobile station (MS) 140 includes a WLAN network card and a subscriber identity module (SIM) card (not shown). The MS 140 registers the GPRS network 120 using the SIM card.
The MS 140 may also register a WLAN 160 using the SIM card. In FIG. 1, the MS 140 transfers an international mobile subscriber identity to an access point (AP) 162 in the form of packets using the SIM card. Then, the AP 162 transfers the international mobile subscriber identity to an access controller 164, which manages registering of the MS 140 and filters the packet transferred from the mobile station, which is not authenticated.
Then, the access controller 164 transfers the international mobile subscriber identity to the verification database 128 of the GPRS network 120 via an Internet protocol (IP) network 180. The verification database 128 obtains the authentication information via the MSC/HLR 126 to manage the registering requirements of the MS 140. When the verification database 128 obtains the authentication data of the MS 140 from the MSC/HLR 126, the verification database 128 transmits the authentication data to the access controller 164 via the IP network 180, and the access controller 164 notifies, via the AP 162, the MS 140 that the WLAN 160 has been successfully registered.
In the architecture of registering the WLAN, the authentication data has to be obtained through the remote MSC/HLR 126 and the verification database 128. So, when the MS 140 is registering the WLAN 160, the transmitted packets containing the international mobile subscriber identity have to be transmitted to the MSC/HLR 126 via the IP network 180 and the verification database 128, and the authentication data has to be transmitted back to the access controller 164 reversely via the same transmitting path. Consequently, the packet transmitting not only reduces the overall efficiency of the network but also increases the end-to-end delay when the mobile station and the mobile station are communicating with each other. In addition, the IP network 180 is an open network, and the packet, which contains the international mobile subscriber identity and is not encrypted, may be stolen when the IP network 180 is transmitting data, thereby reducing the security of the data transmission significantly.